The invention lies in the field of appliances. The invention relates to a household dishwasher with a dishwashing compartment with at least two spray devices that subject items that are disposed in the dishwashing compartment and are to be cleaned to the action of a liquid delivered by a circulating pump.
A household dishwasher is disclosed, for example, from German Published, Non-Prosecuted Patent Application DE 24 28 991 A1. In the case of commercially available household dishwashers, the at least two spray devices are simultaneously charged with the liquid delivered by the circulating pump. In the case of the household dishwasher according to German Published, Non-Prosecuted Patent Application DE 24 28 991 A1, however, to achieve a cleaning result that is equal to or better than that of the commercially available dishwashers outlined above, each spray device is charged alternately one after the other with the liquid delivered by a circulating pump, so that the full pressure of the circulating pump is allowed to act only on one spray device and that a smaller quantity of liquid and lower level of energy for circulating and also for heating the circulated liquid are required. To carry out such a process for alternately charging the spray devices, use is made of changeover devices, usually called water diverters.
European Patent Application EP 05 47 011 A1, for example, discloses the practice of using a hydraulically activated flap valve disposed between liquid-supply lines to the spray devices. The application further discloses alternately opening one of the liquid-supply lines and, at the same time, closing the other liquid-supply lines. The changeover device has a separate housing and is disposed along the course of the liquid-supply lines.
Furthermore, European Patent Application EP 02 37 994 A1, for example, discloses the practice of using a ball in the delivery connection of the circulating pump, which changes position if operation of the circulating pump is interrupted. The application further discloses alternately opening one of the liquid-supply lines and, at the same time, closing the other.
In addition, European Patent 05 85 905, for example, discloses the practice of using a motor-driven, rotating horizontal plate with bores to open one or more accesses to liquid-supply lines and to close others. The changeover device has a separate housing and is disposed along the course of the liquid-supply lines.
The above-mentioned changeover-device solutions are disposed in poorly accessible locations of the household dishwasher and are, thus, difficult to install and/or require a separate housing that has to be disposed in a location of a household dishwasher that additionally restricts the already restricted space conditions of a household dishwasher, e.g., along the course of the liquid-supply lines.
It is accordingly an object of the invention to provide a household dishwasher that overcomes the hereinafore-mentioned disadvantages of the heretofore-known devices and methods of this general type and that has a changeover device, for charging spray devices, disposed in a non-restricting location.
With the foregoing and other objects in view, there is provided, in accordance with the invention, a household dishwasher, including a dishwashing compartment, a circulating pump for delivering liquid to the dishwashing compartment, a flow heater having an inflow connection fluidically connected to the circulating pump and at least two outlet connections, at least two spray devices disposed in the dishwashing compartment and fluidically connected to a respective one of the at least two outlet connections for supplying the liquid to each of the at least two spray devices, the at least two spray devices subjecting items disposed in the dishwashing compartment and to be cleaned to an action of a liquid delivered by the circulating pump, a changeover device for selectively opening and closing the at least two spray devices. The changeover device is disposed at the flow heater upstream of the at least two outlet connections with respect to a liquid flow direction. The changeover device is configured to perform a function selected from selectively opening and closing a respective one of the at least two spray devices alternately one after another, selectively opening and closing a number of the at least two spray devices alternately one after another, selectively opening and closing all of the at least two spray devices alternately, selectively opening and closing a respective one of the at least two spray devices on a permanent basis, selectively opening and closing a number of the at least two spray devices on a permanent basis, selectively opening and closing all of the at least two spray devices on a permanent basis, selectively opening and closing a respective one of the at least two spray devices alternately one after another and on a permanent basis, selectively opening and closing a number of the at least two spray devices alternately one after another and on a permanent basis, and/or selectively opening and closing all of the at least two spray devices alternately and on a permanent basis.
The liquid delivered in the invention is directed from the circulating pump to an inflow connection of a flow heater and through the flow heater. The flow heater has at least two outlet connections for supplying the liquid to different spray devices in each case. The spray devices are to be opened and/or closed by a changeover device that is disposed on the flow heater upstream of the outlet connections, as seen in the flow direction, such that either one of the outlet connections or a number of outlet connections or all the outlet connections are opened and/or closed alternately one after the other and/or on a permanent basis.
Because the changeover device is disposed directly at the outlet of the flow heater present, which is anyway, virtually in extension of the outlet connection, the changeover device is disposed in an easily accessible and non-restricting location of the household dishwasher and, thus, can be installed easily. The invention succeeds in providing a household dishwasher of the type mentioned in the introduction having a changeover device, for charging spray devices, disposed in a non-restricting location. Furthermore, a very straightforward construction of the changeover device is possible by virtue of the configuration of a plurality of outlet connections and the alternating and permanent alternative opening and/or closure thereof by the changeover device.
In accordance with another feature of the invention, the number of outlet connections of the flow heater expediently corresponds to the number of spray devices or simultaneously operated groups of spray devices.
According to a preferred embodiment of the invention, the flow heater has two outlet connections.
In accordance with a further feature of the invention, it is possible for an outlet opening of the flow heater, the outlet opening being disposed upstream of each outlet connection, to be closed by a rotary valve of the changeover device. The rotary valve is disposed upstream of the outlet openings, as seen in the flow direction. The prior art changeover devices described in the introduction also have the disadvantage that they are of complicated construction and, thus, are easily susceptible to malfunctioning. Such a disadvantage is overcome by the preferred feature of the invention because even, for example, deposits of dirt cannot disrupt a closing function of the rotary valve as they are pushed away by the rotating rotary valve.
In accordance with an added feature of the invention, the rotary valve has at least one closed region and at least one region that is open by way of a bore. As a result, there is a straightforward production of the rotary valve.
In accordance with an additional feature of the invention, the rotary valve has, alternately in the direction of circulation in each case, an open region followed by a closed region, between which there is an unfilled space. As a result of the configuration, the production of the rotary valve is further simplified and straightforward control of the circulation of the rotary valve is achieved.
In accordance with yet another feature of the invention, the rotary valve is moved, by a drive device, into at least one position in which the at least one closed region or a number of closed regions closes the at least one outlet opening or a number of outlet openings and/or in which all the outlet openings are open. Thus, the rotary valve can be used for all possible methods of charging the spray devices.
In accordance with yet a further feature of the invention, the rotary valve is advantageously in the form of a propeller blade having two mutually opposite regions and being moved, by the drive device, into a position in which the closed region closes an outlet opening and the open region, having a bore, keeps the respectively other outlet opening open. The configuration is the simplest way of control for the simplest case of a household dishwasher with alternate charging of the spray devices, namely with two spray devices.
In accordance with yet an added feature of the invention, the rotary valve a propeller blade having two mutually opposite regions, one of the opposite regions is a closed region, another of the opposite regions is an open region with a bore, the at least two outlet connections is two outlet connections, the flow heater has two outlet openings respectively disposed upstream of each of the two outlet connections in the liquid flow direction, the rotary valve is disposed upstream of the two outlet openings with respect to the liquid flow direction, and a drive device is connected to the propeller blade for moving the propeller blade into a position where the closed region closes one of the two outlet openings and the open region with the bore keeps another of the two outlet openings open.
In accordance with yet an additional feature of the invention, on the regions, the rotary valve particularly advantageously has encircling ribs that project upwards in the direction of the outlet openings in the installed position and have a semicircular cross section. The ribs achieve good outlet-opening-enclosing abutment of the rotary valve against the inner wall of the flow heater and, thus, good sealing of the outlet opening that is to be closed.
In accordance with again another feature of the invention, the drive device is a motor with a gear mechanism. A motor with gear mechanism is a changeover-device drive unit that can be controlled extremely straightforwardly for continuous changeover in the charging of the spray devices and for changeover that takes longer or for permanent opening of one or more supply lines to the spray devices. Further simplification of the changeover device is achieved as a result of the configuration.
In accordance with again a further feature of the invention, the flow heater has an outlet opening disposed upstream of each of the at least two outlet connections in the liquid flow direction, and a speed of the circulating pump is reduced in periods of time when all outlet openings are open and when the at least two spray devices are continuously and alternately charged.
As described in the introduction, continuous, alternate charging of the spray devices is used, in particular, to save water. In the case of a relatively small filling quantity, however, even with brief operation of the two spray devices, the intake chamber of the circulating pump quickly becomes empty, which then, due to the intake of air, results in an unpleasant and undesirable development of noise in the circulating pump. To prevent such noise, in the case of continuous, alternate charging of the spray devices, the speed of the circulating pump is particularly advantageously reduced in the periods of time where both outlet openings are open. With such a measure, the above-described development of noise caused by the intake of air cannot arise because the intake capacity of the circulating pump is reduced to the extent where the intake chamber of the circulating pump does not become empty.
With the objects of the invention in view, there is also provided household dishwasher, including a dishwashing compartment, a circulating pump for delivering liquid to the dishwashing compartment, a flow heater having an inflow connection fluidically connected to the circulating pump and two outlet connections, two spray devices disposed in the dishwashing compartment and fluidically connected to a respective one of the two outlet connections for supplying the liquid to each of the two spray devices, the two spray devices subjecting items disposed in the dishwashing compartment and to be cleaned to an action of a liquid delivered by the circulating pump, a changeover device for selectively opening and closing the two spray devices. The changeover device is disposed at the flow heater upstream of the two outlet connections with respect to a liquid flow direction. The changeover device is configured to perform a function selected from selectively opening and closing a respective one of the two spray devices alternately one after another, selectively opening and closing both of the two spray devices alternately, selectively opening and closing one of the two spray devices on a permanent basis, selectively opening and closing both of the two spray devices on a permanent basis, selectively opening and closing a respective one of the two spray devices alternately and on a permanent basis, and/or selectively opening and closing both of the two spray devices alternately and on a permanent basis.
With the objects of the invention in view, there is also provided a method for washing dishware including the steps of providing a dishwashing compartment with at least two spray devices disposed therein, fluidically connecting an inflow connection of a flow heater to a circulating pump, fluidically connecting the at least two spray devices to a respective one of at least two outlet connections of the flow heater, subjecting dishware disposed in the dishwashing compartment and to be cleaned to an action of a dishwashing liquid by delivering the liquid from the circulating pump through the flow heater, the at least two outlet connections, and the at least two spray devices, and selectively opening and closing the at least two spray devices with a changeover device disposed at the flow heater upstream of the at least two outlet connections with respect to a liquid flow direction. The changeover device is configured to perform a function selected from selectively opening and closing a respective one of said at least two spray devices alternately one after another, selectively opening and closing a number of said at least two spray devices alternately one after another, selectively opening and closing all of said at least two spray devices alternately, selectively opening and closing a respective one of said at least two spray devices on a permanent basis, selectively opening and closing a number of said at least two spray devices on a permanent basis, selectively opening and closing all of said at least two spray devices on a permanent basis, selectively opening and closing a respective one of said at least two spray devices alternately one after another and on a permanent basis, selectively opening and closing a number of said at least two spray devices alternately one after another and on a permanent basis, and selectively opening and closing all of said at least two spray devices alternately and on a permanent basis.
Other features that are considered as characteristic for the invention are set forth in the appended claims.
Although the invention is illustrated and described herein as embodied in a household dishwasher, it is, nevertheless, not intended to be limited to the details shown because various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.
The construction and method of operation of the invention, however, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.